Recently, there has been much discussion concerning the feasibility of building a flexible system for automatic manufacturing of three-dimensional dies, molds, prototypes and products. Although it is presently possible to develop information about a flat figure or a three-dimensional object in a computer memory and then have that figure or object reproduced in two-dimensional fashion on a piece of paper by incremental movements of a plotter pen, it is not yet possible to actually produce the object in three-dimensions in the same manner. Nevertheless, it would be highly desirable to produce three-dimensional objects from existing computer assisted design systems (CAD systems), since among the benefits to be derived would be reduction in expense and increase in efficiency.
Based upon a consideration of the features of CAD systems, it does not at first appear that there is any logical manner for producing three-dimensional objects of gradually varying shape. Upon further investigation, however, a three-dimensional object might be producible utilizing thin plane cross-sections of a solid body as its building blocks with each of the cross-sections being cut or formed separately. Each cross-section could be cut or formed by a laser located on a positioning "plotter-like" table, or by some other technique such as chemical etching, and then attached to another cross-section using a suitable bonding technique. In this manner, any complex three-dimensional object could be built once its design had been completed with the use of a CAD system.
With this method, only one machine and one tool would be needed for production of the three-dimensional object. The only software required for cross-section generation would be the one that already exists in modern CAD systems, and it would presumably work for any three-dimensional object. Being information intensive, this theoretical technique could easily be incorporated into knowledge-based engineering, design, or model-shop systems.
On a small scale, the three-dimensional production system for creation of prototypes can be established as a computer peripheral. It might also evolve into a device for manufacturing lightweight laminated composite parts which are finding widespread use in our energy-sensitive industrial environment. On a large scale, the three-dimensional production system can perform as a full flexible manufacturing system for making dies, molds, prototypes and products.
Certain discrete components of the suggested three-dimensional production system have been used in applications of various types. Unfortunately, until the present invention, there has been no practical means for combining three components and developing still additional needed components into a complete, workable system. For instance, while laser based manufacturing, CAD systems, and lamination processes are all known, it has remained to combine them into an integrated three-dimensional production system.
The power of lasers utilized in laser cutting machinery allows accurate cuts in metals up to 0.25 inches thick. Moreover, CNC-controlled contouring enables cutting of virtually any shape. The cutting speeds of such machinery can range from three thousand feet per minute for plastic films to as low as a few inches per minute for thick or high temperature metals. Similarly, the use of photo etching techniques to create numerous complex flat plates has been known for years, but has never been utilized as a portion of a technique for creating laminated three-dimensional objects. Also, CAD systems have gained enough sophistication to allow solid body representation. Moreover, some CAD systems can accumulate accurate three-dimensional information along with accommodating sectioning of solid objects. Additionally, some types of laminated dies held together mechanically by bolting or the like have been produced by conventional machining for many years. However, despite advances in lamination processes, it has remained to implement the advantages of automation in three-dimensional production.
The present invention is directed to overcoming the above stated problems and accomplishing the stated objects by providing a unique apparatus and method for forming a composite from laminations.